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1 Fig. Art Pressure reducing valve DVGW approved pressure: max. 25 bar (362,50 psi) Outlet pressure adjustable between 1,5 bar (21,8 psi) and 6 bar (87 psi) Factory pre-set to 4 bar ( psi) Temperature Rating: max 30ºC (86ºF) water; Installation position: any With Pressure Gauge Connections 1/4 on both sides and strainer Nominal Diameter Dimensions in mm Maximum flow in m³/h (at 2m/s) Maximum flow in m³/h (at 3m/s) A L (mm) L1 (mm) l (mm) H (mm) D (mm) Residential DIN EN 1567 Industriel DIN 1988 DN 15 G ½ ,3 1,8 DN 20 G ¾ ,3 3,3 DN 25 G ,6 5,4 DN 32 G 1 ¼ ,8 8,6 DN 40 G 1 ½ ,1 13,7 DN 50 G ,2 Application The pressure reducing valve Type 515 is used for reducing pressure in systems with media as given in the specifications below. It is mainly used in domestic water supply, according to DIN Design The IMT range of pressure reducing valves has been specifically designed for applications that require substantial flow capacity with accurate pressure control. The valves are designed for durability whilst being compact and easy to service. The body is manufactured in bronze and the one piece, fully serviceable cartridge in high grade engineering plastics. The valves have integral, serviceable strainers and include test/gauge points as standard. The valve can be supplied in adjustable and fixed settings over range between 1,5 and 6 bar. The ½ to 2 have one piece replaceable cartridges that can be removed, cleaned and replaced with ease. IMT ARMATUREN AG Sonnenstr CH-9434 Au Tel Fax

2 Pag. 2 Art Installation The connection size depends on the required flow rate capacity. When choosing a pressure reducing valve, it has to be taken into consideration that a pressure drop of 1.1 bar occurs at maximum flow rate. This is the difference between the static and the dynamic pressure on the outlet of the pressure reducing valve. When a defined flow rate is required for a determined draw-off point, the setting of the pressure reducer has to be calculated beforehand. A pressure reducing valve works without auxiliary energy with very little adjustment forces. For this reason it reacts sensitively to impurities. A filter installed upstream protects the pressure reducing valve. The special cartridge design allows any mounting position. Maintenance The pressure has to be set at static pressure. Loose the safety screw in the adjustment handle. The requested pressure is set with a flick of the wrist. With the well-contrived combined adjustment-display handle, the pressure reducer not only ensures an optimal pressure but also allows to read the set pressure without an additional pressure gauge. To reduce the outlet pressure, turn the adjustment handle in the direction of the minus symbol (-). To increase it, turn the adjustment handle in the direction of the plus symbol (+). Thanks to the special design of the cartridge system the disassembling of the operational parts of the pressure reducing valve is extremely easy and possible without disassembling the pressure reducing valve itself and without using special tools. Material The body is made of bronze. All rubber parts are made of high quality elastomer. The diaphragm is reinforced and the high resistance of the screw cap is due to the glass fibre reinforced synthetic material. Advantages Version Art. 515 DVGW approved Installation position: any Bronze body Screw cap of glass fibre reinforced synthetic material With pressure gauge connections 1/4" on both sides and strainer Outlet pressure indicator replaceable cartridge with Hose Unions on both sides All synthetic parts getting in contact with water are approved by the German Public Health office (KTW). IMT ARMATUREN AG Sonnenstr CH-9434 Au Tel Fax

3 Pag. 3 Art. 515 Pressure control: solving water system problems The water systems in domestic, commercial and industrial properties can present unique problems and challenges as plumbing fittings become ever more sophisticated. The water supply pressure in the UK can vary from 1bar to 20bar (or even higher in some low usage areas). The water pressure will also tend to vary through the day, for instance at high usage times (typically mornings and late afternoons) the pressure may drop by comparison with low water usage times (throughout the night, for example), when the pressure may increase dramatically. Such periods of high pressure can cause several problems: excessive noise from high flow velocities, water hammer from quick closing taps or solenoid valves, plus the risk of water wastage is particularly great because higher pressure means higher flow rates. The water supply usually enters domestic dwellings beneath the kitchen sink so the first effect of high pressure is often experienced at that point; when the cold tap is turned on too quickly or too far, this creates a gush of water which hits the bottom of the sink and bounces back, soaking the user and creating a wet mess! The best way to control high pressure is by installing a pressure reducing valve. These take a high pressure at the inlet, then the valve reduces it to a lower pressure at the outlet as desired, under both flow and no-flow conditions. Pressure adjuster Pressure Valve housing Outlet Comb Valve Valve seat How do pressure reducing valves work? A pressure reducing valve is a valve which takes a high inlet pressure and reduces it to a lower outlet pressure. When it does this under both flow and no-flow conditions, the type of control is known as drop tight. IMT s pressure reducing valves use a balanced spring and diaphragm to control the downstream pressure. This drop tight feature is one of the most important criteria for any pressure reducing valves, as this stops the pressure from creeping - a term which is used when an increase in the downstream pressure occurs under no flow conditions. A valve which will allow this creep cannot be known as 'drop tight' or in fact a true pressure reducing valve, as it will IMT ARMATUREN AG Sonnenstr CH-9434 Au Tel Fax

4 Pag. 4 Art. 515 eventually allow the pressure to creep up to equal the upstream pressure, which can cause significant problems and essentially negates the point of using a pressure reducing valve in the first place. The diaphragm effectively separates all of the water contact parts and the pressure from the water supply away from the control spring and associated mechanism. The body is then protected from debris by the use of a stainless steel strainer (as shown in the cutaway drawing below). Pressure Reducing Valve in closed position Outlet/s closed causing back-pressure Comb Valve closed Under no flow conditions the downstream pressure puts back-pressure on the seat and diaphragm of the valve, which in turn overcomes the spring pressure. This means the seat moves up, forcing it to seal against the diaphragm, therefore not allowing the downstream pressure to increase. Pressure Reducing Valve in open position Outlet/s open Comb Valve open Under flow conditions the back pressure against the seat is reduced thus allowing the seat to open and water to flow through the valve. IMT ARMATUREN AG Sonnenstr CH-9434 Au Tel Fax

5 Pag. 5 Art. 515 Unique Cartridge Design How to size a PRV This is predominantly based on two different criteria: application and flow rates. Application describes the type of property the valve is to be used in: whether it is commercial/industrial or a domestic installation. All All AII\ure IMT reducing pressure valves reducing use a valves cartridge use system. a cartridge The system. cartridge The houses cartridge all working houses all working components of the pressure reducing valves: strainer, spring, diaphragm and seat. The cartridge format makes servicing or replacement of the valves as simple as possible. Each pressure reducing valve cartridge can be removed for servicing of the integral stainless steel strainer, which is situated at the base of the cartridge to protect the seat of the valve. If unprotected, debris could cause poor flow rates and even hold the seat in the open position thus preventing the pressure reducing valve from working properly. As all working components are incorporated in the one-piece cartridge, it continues to ensure that the set pressure is kept whilst servicing is being undertaken. Other valves may need to be re-commissioned after each service or, if they include several different components, it is easy for these to be misplaced. The cartridge system means complete replacement cartridges can be used for maintenance or repair, which minimises site down time and means only one spare cartridge needs to be held in stock rather than several small components. Some pressure reducing valves can be extremely noisy and cause annoyance, but each IMT reducing valve has been checked to ensure that any noise created does not exceed the 20dB limit: this is classed as a whisper on a decibel scale. Low noise is incorporated within the valve design so they comply with the European standard Class 1 BSEN The base of the cartridge has been specifically designed so that water will disperse, and thereby minimise noise. The comb also has a second significant purpose: by dispersing the water passing through the valve it alters the water flow turbulence, and this in turn reduces cavitations on the body of the valve. Flow rate is the most important factor for sizing a pressure reducing valve. Sizing a valve incorrectly can cause several problems; if oversized the valve seat may open for a very small flow rate, which may occasionally be acceptable but over a long period of time can result in a wire drawing across the valve seat. A wire drawing occurs when the valve disc and seat position operate close to the shut-off point of the valve for extended periods of time. This then means the water flow scores a pathway in the seat material which remains when the valve closes tight to the shut-off position and allows a little flow and pressure to creep through the valve. To calculate the flow rate you must work out how many outlets are required and what the combined maximum flow rate for these will be. You can then use the table to ascertain which size valve is required. For larger commercial applications various sizing solutions can be used: for example, if the flow rate is lower at some times than at others then using several smaller size PRVs in parallel may be more practical, or use one smaller valve as a bypass thus allowing water to flow easily through the valve when the flow rate is lower than normal, without causing either wire drawings or creating noise across the valve, as previously mentioned. Pressure Reducing Valve Sizing Guide Residential Building Commercial Building Size DN Max flow rate Vs Max flow rate Vs l/s l/s IMT ARMATUREN AG Sonnenstr CH-9434 Au Tel Fax